Construction of an arginine enzyme electrode and determination of arginine in biological materials

The arginine electrode is based on a coupled enzymatic system consisting of arginase and urease with an ammonia gas sensor; conditions of immobilization are optimized. Arginine in the range 3 × 10^?5–3 × 10^?3 M gives a linear potential vs. log (concentration) plot with a response time of 5 min over the range specified. Several compounds structurally related to arginine do not interfere. The method is suitable for the determination of arginine in bovine insulin and human serum. Results compare well with values given in the literature or obtained by the conventional Sakaguchi method.